Regulating low-pressure turbines.



L. GUBELIG.

REGULATING LOW PRESSURE TURBINBS.

APPLICATION FILED SEPT. 30, 1913.

Patented Apr. 21, 1914 Inventor- Ludwig Cube! Witnesses v COLUMBIA PLANOGRAPH C0..WAsHlNuTON, D c.

UNITED STATES PATENT OFFICE.

LUDWIG CUBELIC, 0F CHARLOTTENBURG, GERMANY, ASSIGNOR T0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

IREGrTJ'LATING LOW-PRESSURE TURBINES.

To all whom it may concern:

Be it known that I, LUDWIG OUBnLIo, a subject of the King of Prussia, residing at Charlottenburg, Germany, have invented certain new and useful Improvements in Regulating Low-Pressure Turbines, of which the following is a specification.

This invention relates to a device for regulating the low pressure steam flowing from one or more auxiliary engines or industrial heating appliances to an intermediate stage of a main multistage turbine.

The object of the invention is to control the supply of low pressure steam by means of the pressure in the said intermediate stage acting against an adjustable regulating device. The result is that in case the load on the main turbine drops below a predetermined minimum, as by reason of the circuit breaker of the generator opening and causing the speed governor to shut off steam from the high pressure source, then the pressure in said intermediate stage, due to the condenser, also drops to such a point that my improved regulator will open a passage permitting the escape of said low pressure steam from the auxiliary source and thus prevent the engine from racing. Instead of opening an escape pipe, the reg ulator may shut off the flow of low pressure steam.

The accompanying drawing is an elevation, partly in section, of a turbine equipped with my invention.

The main multistage turbine 1 receives high pressure steam through the governing device 2, and exhausts by way of the conduit 3 to a condenser. A pipe 4 is connected to an intermediate stage of the turbine, and is supplied with low pressure steam from the exhaust of an auxiliary engine, a heating system, or other source. From the pipe 4 a branch pipe 5 leads to the condenser or to the atmosphere. This branch pipe 5 is controlled by a valve 6 which opens away from the pipe 4. The stem 7 of said valve runs through a stuffing box 8 to a movable abutment exposed to the pressure in the upper part of the pipe 4, which is practically the same as that in the intermediate stage of the turbine with which said pipe communicates. In the drawing the movable abutment takes the form of a piston 9 Working in a cylinder 10, and having its lower side exposed to the pressure in pipe 4: by means of the passage 11. The

Specification of Letters Patent.

Application filed. September 30, 1913.

Patented Apr. 21, 1914:.

Serial No. 792,586.

weight of the valve, stem and piston is counterbalanced by a spring 12 underneath said piston. The chamber above the piston is open to the atmosphere, or to the condenser, as may be desired. A spring 13 exerts a downward pressure on the piston in opposition to the lifting force of the fluid pressure beneath it. The tension of the spring 13 can be adjusted by means of a screw-threaded plunger 14 meshing with screw-threaded aperture in the cap 15 of the chamber housing the spring 18. The plunger can be rotated by the hand wheel 16.

The operation is as follows: With sumcient load on the turbine, the valve 6 remains closed, and all the low pressure steam passing through the pipe 4: flows to the intermediate stage of the turbine and assists in carrying the load. But if the load drops below a predetermined minimum, then the speed governor 2 shuts off the high pressure steam, and the pressure in the intermediate stage of the turbine becomes less than that of the low pressure steam supplied to the pipe 1-. The low pressure in the turbine casing is immediately communicated to the cylinder 10 and permits the spring 13 to force down the piston 9 and open the valve 6. This affords a vent for the low pressure steam, so that it no longer enters the turbine, and thus all danger of racing is obviated.

hen the load comes on again and the pressure in the intermediate stage rises by reason of the opening of the high pressure valves, the valve 9 is lifted and shuts off the pipe 5, so that all the low pressure steam from the auxiliary is supplied to the main turbine again to assist in carrying the load.

By suitable adjustment of the spring 13, it is possible to select any desired pressure at which the valve will open.

In accordance with the provisions of the patent statutes, I have described the principle of operation of my invent-ion, together with the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative, and that the invention can be carried out by other means.

What I claim as new and desire to secure by Letters Patent of the United States, is,

1. The combination with a multistage turbine, of a pipe conveying low pressure steam to an intermediate stage thereof, an escape pipe opening from the low pressure steam pipe, a valve controlhng said escape pipe,

and a movable abutment connected to said valve and exposed to the pressure in said intermediate stage, such pressure acting on said abutment to hold said valve closed and means for opening said valve when the pres sure falls too low.

2. The combination with a multistage turbine, of a pipe conveying low pressure steam to an intermediate stage thereof, an escape pipe opening from the low pressure steam pipe, a valve controlling said escape pipe, a movable abutment exposed to the pressure in said intermediate stage and acting to hold said valve closed, and an adjustable spring for opening said valve When the stage pres sure drops below a predetermined value.

3. The combination with a multi-stage turbine, of a pipe conveying low pressure steam to an intermediate stage thereof, an escape pipe opening from the low pressure steam pipe, a valve controlling said escape pipe, a cylinder, a piston in the cylinder, a valve stem connecting the valve and piston, opposed springs in said cylinder acting on opposite sides of said piston, and means for subjecting one side of said piston to the pressure in said intermediate stage.

In witness whereof, I have hereunto set my hand at Berlin this 9th day of Septem- Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents Washington, D. G. 

